Still not much out of the LCROSS team, victims of “HYPErspace” to say the least. Let’s entertain ourselves in the intervening time with a Forbes.com article “Bombing the Moon“. And for those in a hurry:

The LCROSS mission is an important and expensive scientific experiment. Nonetheless, comments on Web sites such as Scientific American and Nature indicate that quite a few people thought the whole venture to be some sort of outer-space vandalism. Some even wondered whether NASA might have acted illegally or violated an international law or treaty by setting out to “bomb the Moon.”

The answer is no. But while many might be surprised–dismayed, even–to hear that there is such a thing as “space law,” there are treaties governing activities in outer space, including the Moon.

One can only feel sad upon reading Giovanni F Bignami’s op-ed piece about the race to the Moon and what choices to take for the future (“Once in a Blue Moon “, IHT, 18-19 July 2009). Prof Bignami’s argument appears to be about treating space-faring as a purely novelty product, like a fairly curious but ultimately useless item on a late-night TV shopping channel. Something you may be convinced to buy, but just the once.

And even if we have spent less than a week in total time exploring a few square miles of a place as big as the former Soviet Union, Prof Bignami tries to seriously argue that there is no “compelling reason” to go back to the Moon. And that we should embark on the enormous effort to reach Mars instead, presumably for a couple of trips before getting bored with travelling millions of kilometers too.

Here’s a “compelling reason” then: as it is well known, one needs a lot less fuel to travel to Mars from the Moon, than from Earth. Most of the launch cost lies in getting from our planet to low Earth orbit: beyond that, the whole planetary system is within relatively easy reach.

Prof Bignami remarks also that “the notion of mining on the moon would also [be] environmentally offensive“. I for one do not understand how will humans ever be able to “environmentally offend” a surface pummeled for billions of years by asteroids of all sizes, by a perfectly unhindered solar wind, and by cosmic radiations of all sorts. That is the Lunar surface, made of a type that likely covers several billion square kilometers on hundreds of natural satellites in our Solar System alone.

Paradoxically, the astronomical/astronautical community has been unable to support its own cause since the launch of the Sputnik. Nobody has gone anywhere because of effective lobbying by planetary geologists or solar scientists.

Bignami’s op-ed appears to be yet another example of how bizarrely brainy arguments about going to Mars vs returning to the Moon have succeeded so far only in keeping the human race in low Earth orbit, literally going around in circles instead of literally reaching for the stars.

The following text, by Stephen Ashworth FBIS, has been presented at the British Interplanetary Society’s “Ways to Mars” symposium, held on 19 November 2008 at the Society’s London headquarters. Its main points:

– Most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials, and that is already in space, and already in orbits very close to the ones which we need;

– But this near-Earth asteroidal resource is completely invisible to the space agency paradigm of space exploration, because [the paradigm] excludes the construction of permanent human activity in space.

Transport for Areopolis Or: “Implications of the Choice of Economic Paradigm for Strategies of Manned Access to the Moon and Mars” by Stephen Ashworth

When considering human access to Mars, it seems to me that there are two key points which need to be taken into account, but which are often ignored. I shall offer you these two points very shortly.

Designs for manned missions to Mars typically involve assembling in low Earth orbit a spaceship weighing several hundred to over a thousand tonnes.

For example, each Troy spacecraft, which we shall be hearing more about this afternoon, weighs nearly 800 tonnes to carry 6 astronauts. The “space lego” nuclear powered Mars mission uses two ships of 240 tonnes each, thus a total of 480 tonnes in low Earth orbit. [I was wrong — this turns out to come to a total of 955 tonnes.] The “magic” Mars mission requires five Energiya launches, thus probably weighs 4 to 500 tonnes when ready to go.

Meanwhile the official European Space Agency design study for a Mars mission proposed a ship, again for 6 astronauts, which required 20 Energiya launches for every single Mars departure. These launches would build up a ship weighing 1357 tonnes at departure.

The Mars ship in low Earth orbit thus weighs between about 50 tonnes and about 200 tonnes per astronaut on board. Launching such large masses into orbit for the benefit of so few people is one reason why manned Mars exploration is hopelessly uneconomic.

At present-day cargo rates to low Earth orbit of $10 million per tonne, this is a billion dollars per astronaut, plus the cost of the Mars hardware itself. Even at spaceplane rates, which may fall to as low as $10 thousand per tonne, this is still a million dollars per astronaut, plus the cost of the hardware.

At these rates, there will not be many people going to Mars.

Let me show you an Earth-Mars transfer orbit.

Orbit of Earth, orbit of Mars, and an elliptical orbit which intersects both of them

Here is an orbit which reaches out from Earth to pass the orbit of Mars. It has about the same size and shape as the orbit of an Earth-Mars cycler, such as the ones being studied by Buzz Aldrin and his collaborators.

It might therefore be the orbit of a future manned Mars vehicle. But that’s not what I drew. What I’m showing you here is the orbit of minor planet 4660 Nereus.

The concept of an interplanetary cycler, which repeatedly encounters Earth and Mars, goes back to the early 1980s. Alan Friedlander and John Niehoff first proposed setting up long-lived space habitats which remain permanently in interplanetary space. These would periodically be used for transporting people between Earth and Mars. Relatively small ferry spacecraft would complete the transport chain between the cycler and a local parking orbit or planetary surface.

In 1985 Buzz Aldrin added the concept of a gravity assist at each planetary flyby. This technique allows a cycler to stay in phase with the relative motion of Earth and Mars. It enables it to offer passage between these planets once every 2.14 years, the Earth-Mars synodic period.

A great number of near-Earth asteroids, such as 4660 Nereus, resemble natural Earth-Mars cyclers. A proportion of them are believed to be carbonaceous chondrites, containing water and other volatiles. Water in space is of incalculable value as a feedstock for propellant manufacture, as a near ideal substance for radiation shielding, and for other life support functions.

I have checked the online listings of near-Earth asteroids published by the Minor Planet Center. Applying quite stringent orbital criteria, I found a total of 56 Amor and Apollo asteroids which behave like natural Earth-Mars cyclers. New ones are being discovered all the time — for example, of those 56, ten were only identified this year.

Now to my two key points.

Firstly: most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials. That mass is already in space, and already in orbits very close to the ones which we will need to reach and return from Mars. It does not need to be launched from Earth. It can be mined in situ.

So why is hardly anybody getting excited about this? Why does it not form the basis of the Constellation programme, or of the recent ESA or Russian design studies, or even the magic, the trojan or the space lego Mars missions?

Because of my second point: the asteroidal resource is completely invisible to the space agency paradigm of space exploration. That mode of planning excludes the possibility of systematic use of natural in-space materials, and it excludes the construction of permanent infrastructure on Earth-Mars cycler orbits. It will not contemplate anything that suggests permanent human activity in space.

I think we can identify two broadly contrasting attitudes to transport infrastructure.

The heroic paradigm is only interested in special missions of heroic exploration. This is the space agency mode of thinking. Its prime goal is national presige, under a fig-leaf of science, spinoff and educational inspiration. Think of the Apollo programme. Further back in history, think of Zheng He’s epic voyage of exploration around 1421, from a China which was about to close in on itself.

In contrast with the heroic paradigm, we can identify the systemic paradigm of transport infrastructure. The prime goals here are permanence, growth, and economic profitability. Think of the Cunard and White Star steamers which connected Britain with the Americas and the Empire from the mid-nineteenth to the mid-twentieth century.

Now obviously, since there is currently nobody on the Moon or Mars, the next people to travel there will of necessity be heroic government explorers. But the question we need to address is this: will their transport system be designed for cancellation, like Apollo, or will it be designed for growth, like Cunard?

Secondly, it will not be content with a single route — say, between Kennedy spaceport on Earth and a single base at Utopia Planitia on Mars. It will rather seek to foster a network of different routes among a number of different transport nodes. Those nodes may include an increasing number of space hotels, factories and laboratories, and lunar and martian bases.

Note particularly that the use of transport nodes allows in-space refuelling. This capability was regarded by early spaceflight theorists such as Hermann Oberth and Guido von Pirquet as essential if lunar and martian flights were to become achievable using chemical fuels.

Thirdly, a systemic space transport system will diversity its sources of propellants and life support materials, exploiting the transport nodes for in-space refuelling.

Fourthly, it will not be content with a pillar architecture, but will develop a pyramidal one. In a pillar architecture, one unique space station is succeeded by one unique Moon base, and that in turn by one unique Mars base. In a pyramid architecture, by contrast, it is growth in the use of space stations that supports the first Moon base, and growth in the use of Moon bases that supports the first Mars base.

Thus in impressionistic figures, if there are ten people on Mars, then we should expect to see at the same time at least a hundred people on the Moon, and at least a thousand on board stations in Earth orbit at any one time.

So we can now design a Mars transport system along the following principles:

— The long-haul journey is accomplished on modular interplanetary cycler stations, which are upgrades of stations in regular use as Earth-Moon cyclers, which are themselves upgrades of stations in regular use in low Earth orbit as hotels, factories and so on;

— The transport chain between Earth and the interplanetary cyclers is closed by short-range ferries, which are upgrades of ferries in regular use to connect with the Earth-Moon cyclers, which are themselves upgrades of ferries in regular use between Earth’s surface and low Earth orbit;

— The bulk of the development work that goes into the first Mars mission is carried out by commercial companies in pursuit of profitable business in space tourism, manufacturing and energy;

— As a result of growth in traffic in the Earth-Moon system, an in-space refuelling system based on near-Earth asteroidal water will become economically viable, vastly decreasing launch costs from Earth.

There may still be a heroic attempt to get to Mars in isolation from the development of such a space economy. If we are lucky, it will be like Apollo, and will be cancelled after the first few landings. If we are unlucky, it will be like the X-33 or Hermès spaceplanes, or like the Soviet Moon-landing programme, and be cancelled before its first landing.

Either way, it will not produce much progress towards sustainable human access to Mars. That can only be achieved by a systemic transport system, not a heroic one.

To conclude, I would remind you of my two key points:

— Most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials, and that is already in space, and already in orbits very close to the ones which we need;

— But this near-Earth asteroidal resource is completely invisible to the space agency paradigm of space exploration, because it excludes the construction of permanent human activity in space.

Apollo 10’s Lunar Module, called “LM 4″ or “Snoopy”, is quite remarkable but nearly always forgotten against the much more glamourous Apollo 11 “Eagle”. Despite of that, “Snoopy” is quite fascinating in its own way:
(1) it is the only one of the real flown Apollo LM’s which still is somewhere out in space. All other LM’s burned up in earth’s atmosphere (Apollo 6, 9, 13) or were crashed into the moon, whether intended (Apollo 12, 14-17) or not (Apollo 11).
(2) LM 4 “Snoopy” up to now is the only spacecraft ever launched from moon orbit towards a sun orbit.
(3) “Snoopy” up to now is farthest out in space of all (former) manned spacecraft. In its heliocentric orbit it is as far as 2 AU from earth (during earth opposition)
(4) Apollo 10 and Apollo 12 share the record of the biggest number of real flight hardware objects left over by any of the Apollo missions (three major objects). Apollo 10’s are LM “Snoopy”, CM “Charlie Brown” and S-IVB 505. (As with most of the LM’s, the S-IVB’s of Apollo 13-17 were crashed into the moon; the S-IVB’s of Apollo 8-12 are the only ones sent to solar orbit. BTW, Apollo 12’s S-IVB came back in 2002 as object “J002E3″).
So, Snoopy really is a quite lonesome record-holder.

It is really fascinating to think there is a piece of late-1960’s Apollo hardware flying around the solar system, awaiting for the day when we’ll finally go out and return it home.

There are two main problems with “moon hoaxers”: one, as Plait pointed out, is that they choose to tell only that part of the truth that suits them. The second, if I may add, is that they invariably never ever reveal what evidence would convince them to change their mind.

=================

I have only one remark for the Bad Astronomer: sometimes he goes too hard for it. All Moon-hoaxers’ claims I have seen so far are already ridiculous enough. Is it really necessary to build jokes around stuff that is already laughable on its own?

In the meanwhile, in 46 years of interplanetary travels there have been only a couple of Russian attempts at studying Phobos, the satellite of Mars that is likely to be a captured asteroid.

And none at all about Deimos, the other satellite of Mars, despite the fact that it is the easiest and cheapest place to reach in the Solar System from the Low Earth Orbit (such as the Space Station’s). It’s easier and cheaper than the surface of our own Moon.

Can’t anybody else see a pattern emerging? Yes there have been peculiar missions like the one to asteroid Eros, but those are by far the exception.

Let’s face it: Big Space Agencies don’t like to bother with small components of the Solar System. It is not “cool” enough to say “Well guys and gals we are going to see a space rock smaller than Rhode Island” (despite the surprises those space rocks may be hiding for us to discover).

There is a mission en-route to Pluto now. It was cancelled before lift-off at least once, and I am sure it would have never been approved had Pluto been demoted to “dwarf planet” in that silly astronomical congress a few months back.

========

And all of that, just to make sure schoolchildren could keep a mnemonic of 8 planets?

It was refreshing to see Dwayne A. Day start his “Outpost on a desolate land” article with pragmatic words about calendar slippages in NASA’s return to the moon (on the British Interplanetary Society’s “Spaceflight” magazine, May 2007).

One has just to look at the history of the Space Shuttle and then the International Space Station, compared to the Apollo project, to understand that big space projects without fixed deadlines will cost a lot more than anticipated, and achieve (much later) a lot less.

Some say that’s the way Governments work.

Is there perhaps a case for launching a “Moon Landing” competition, with a prize for whomever will guess the date of the “seventh American landing” (and another for the “first Chinese landing”)?

My entries are the following:

a. Without another Space Race, NASA will finally land again on the Moon on July 11, 2069 (mostly, to avoid feeling ashamed of themselves)

b. With a Space Race with the Chinese, American astronauts will walk on the Moon around July 11, 2029

c. Chinese taikonauts, if things get serious, will reach the Moon around July 2027

Nothing to be enthusiastic about, but what’s the point of deluding ourselves into believing that things will be any faster?

Unless there is some major breakthrough in commercial space activities beyond LEO…

As correctly pointed out by Larry, the issue is that thinner shielding with aluminum-reach lunar regolith could actually be more harmful than beneficial. Fast-moving energetic particles raining from space and hitting too thin a layer of regolith would generate slower but not stop “secondary emissions” that would then interact more with human tissues such as the blood.

As plastics or water stop the radiation particles with considerably fewer “secondary emissions”, they may provide more protection with considerably less thickness.

It turns out that space projects allow for Astronauts to be cooked with a maximum of 50 rem/year. Somehow, this 100-fold increase on what our bodies were evolved to tolerate is not expected to cause much harm.

Perhaps, the very people that suggest that, they should be volunteered for experiments as human guinea pigs.

It took the whole of 19 years between the 1963 space flight of Valentina Tereshkova and that of another woman (Svetlana Savitskaya in 1982).

That gap was due no doubt to compounding of a male chauvinist Soviet society on top of all the issues encountered during her Vostok 6 flight, clearly only few of them even remotely attributable to her own fault: wrong orbit, problems in handling the equipment, Space Adaptation Syndrome including vomiting, unbearable pain, low food consumption, radio silence, etc etc.

It could have easily been predicted that those issues would become the excuse to ground female astronauts for decades, and that’s exactly what has happened.

Move forward now to 2007 and to the abysmal tragedy of Lisa Nowak, the NASA astronaut with more experience in maneuvering the Space Shuttle’s robotic arm than her own emotions.

Perhaps there is less chauvinism now than in the mid-1960’s…but only time will tell if the Nowak Affair will not become the excuse to prevent women to fly to the Moon until much, much later this century.

Bigelow is right and wrong at the same time. If we seriously consider going back to the Moon, resources should be spent investigating how easy it will be to bury those Habitats (inflatable or otherwise).

But excavated regolith is only one option and not the most practical one given the amounts of soil that will have to be moved to make comfortable living out of a stay on the Moon.

Other ideas involve lava tubes, of which there should be aplenty, and artificial giant caves. Especially the caves should be easy to create with explosives, if there is no water in the lunar rocks.

(an edited version has been published in the Journal of the British Interplanetary Society, Vol. 58, No. 3/4 March/April 2005, pp 131-137)

The aim of this presentation is to define the basic reasons, means and timescale for the establishment of a permanent, manned lunar settlement. Going beyond a review of the vast existing literature on the subject, the underlying goal is a call into action (=launches) to all people and organisations involved and interested in the exploration and use of the Moon:
· the BIS
· the Planetary Society
· all Moon-related Societies (such as the Artemis Society)
· every single Lunar and Planetary scientist and
· for reasons that frankly should be obvious to everyone, also the Mars Society

Introduction

Structure

This work is structured into three main sections, plus introduction and conclusions:
· Why go to the Moon? What are the reasons for sending humans?
· What are the technologies needed? Where will the settlements be located?
· When will the human race go back to the Moon? And when can we expect a permanent lunar settlement to be established by?

Background

A few points of note to explain the main assumptions: first of all by "human settlement" it is intended a self-sustaining permanently-manned colony, inhabited not only by scientists and astronauts. In the sense of being opposed to the idea of a "lunar outpost", the structure must be as far as possible from the old concept of "habitable tin cans" ('a la International Space Station).
Furthermore, there have been centuries of Moon-based dreams, for the past five decades or so with some technological flavour [1]. Practically, we do have the Apollo missions, with an equivalent extra-vehicular activity of around 7dd field work at most (more like 3 days, mostly by non-scientists) [2]. Apart from that, and some Soviet missions, it has all been a matter of dreams. The present work aims instead to be all about being pragmatic in the extreme, keeping also in mind that there IS an obvious conflict-of-interest: as one of the Author's goals is to be a member of the lunar settlement; thus helping oneself while helping humanity make use of the Moon.

Issues and Obstacles

Pragmatism means starting from the obstacles between us and the permanent lunar settlement. Very briefly, where is the interest in a new lunar adventure? [3]:

· There is no shortage of grand plans on paper (for example a Lunar Hilton Hotel) and of good ideas about living on the moon, left to collect dust whilst new projects are sketched (thus lowering ever more the likelihood that any of them is put in practice.
· Whatever plan is put forward, it will have to cope with the fact that space flight has always served a political mixture of civilian and military purposes [3]. And when the Apollo lost its political rationale, it was fully cancelled [4]
· A recent example is the amount of duplicated efforts in the R&D for the ISS, or the sorry story behind the stored "GoreSat" having had the wrong sponsor at the wrong time
· At this point in time, there is no political "lunar constituency" [5]. Some quote "Been there, Done that": since Apollo has shown that we can achieve the goal of reaching the Moon, there is little reason to do it again
· Despite earlier ideas there is no strategic military importance in a Moon base [1]. And the scientific environment has not been united (as reported for example by Spudis [6] about the Clementine Mission, and in the obnoxious, baffling "Mars vs. Moon" saga)
· Finally, the attributes usually associated the Lunar environment include hostile, harsh, extreme and dead. As a consequence it is generally believed that it is "very difficult to set up a base there" [7]. In other words, the Moon IS seen as a single patch of rather uninteresting desolated land. It can be explained with the dominating grey hues from the Apollo surface TV transmissions, but still as we will see it is based on a misunderstimation of all the Moon can provide.

Challenges

The establishment of a Lunar colony will include challenges beyond the resolution of the issues listed above:

· Permanence implies a sustainable Lunar economy. But without practical experience the field of lunar economics can only remain in the theoretical space
· There is a non-zero chance that simply the return will be indefinitely postponed. What will that mean [8], and how can we minimise that risk?

Pragmatism on the other hand cannot mean keeping a negative outlook. Let's remember that whatever task we want to achieve, it is by all means much simpler than what presented at the time when President Kennedy promised to land a man on the moon and return him safely within the decade [9].

WhyWhat makes the Moon unique? What are the reasons to go back to our natural satellite, and why with humans? For some reason, those reasons are not actually obvious, despite countless books, articles, conferences in the past.

One could argue that if the reasons were that clear, somebody would have done it already.

Astronomy

There is something that really makes the Moon a unique place in the whole Universe: the Far Side, permanently shielded from Earth by hundreds of kilometres of rock. There is no other place anywhere else that combines radio silence from the cacophony of terrestrial transmission and access to atmosphere- and ionosphere-free skies in the absence of a magnetic field.
The lunar Far Side is thus one of the best places to investigate what is invisible to terrestrial astronomy, that is most of the EM spectrum [10][11]. One example is in the very-low frequency bands [12], where we literally have never collected any data at all.
An advantage of using the lunar surface over orbit-based telescopes is also the possibility of setting up large interferometers without having to develop extremely precise formation-flying controls.
Another example that has been suggested is neutrino astronomy, especially with energies between 1GeV and 10TeV, where the background noise is reduced on the Moon compared to the Earth, Whole-sun neutrino observation would be possible [13], a rather important activity given the somewhat still quite open-to-debate theories about the amounts and types of solar neutrinos.

Lunar, Terrestrial and Solar studies

Obviously, a settlement on the Moon would also provide a great opportunity to understand more about the Moon itself. After all only a few acres have been explored in detail, so there is still plenty that needs to be studied. We miss information both about peculiarities (what is exactly the bright soil at "Reiner Gamma" made of?) and the overall conditions on the Moon (e.g., if the Moon's rocks have been formed in absence of water, what was/is the composition of volcanic gases [14]?). By having a lunar settlement, we can understand that and more, without having to bring rocks and samples back to Earth [15].
Those studies need not only have a local relevance. Apart from the Moon being as good a base as any for the discovery and tracking of Near-Earth Object, due to the amount of data collected during the 1960's the Moon is THE reference for planetary science [16] [17], a differentiated body with significant episodes of volcanism and plenty of crater types, where very little (if anything) is changing now.

There are even open Earth geology questions that can be better answered on our natural satellite. We do have a practical result in this field already. The post-Apollo mainstream lunar origin theory (an impact between proto-Earth and a Mars-sized body) does explain the excess iron in our own siderophile mantle [18].
One of the most interesting, relevant and important questions to ask on the Moon is, has Earth undergone recurring asteroidal/cometary "bombardments"? This has also biological consequences. Whilst traces are hard to find on our planet, the verdict should be well preserved in the lunar soil, starting with the impact crater frequency curve [19][20][21].
The same lunar soil's regolith contains also an at-least-billion-year-long record of the solar activity [22] [23] [24] that would help a lot in the understanding of the behaviour and evolution of our star. Just as well, buried regolith deposits are expected to preserve traces of the very young Sun [25]. Still, no need to stop there: the regolith of permanently shadowed craters at either Lunar pole may contain our best chance to read about the history of the Galaxy.

Exploration/exploitation of the Solar System

Thanks to its low surface gravity, the Moon can be considered a natural interplanetary spaceport. It is much less energy-consuming to go from there than from the Earth to any place in the Solar System (apart from terrestrial surface), including, paradoxically, to Low-Earth Orbit (LEO) [26] [27].
The Moon can then become a source of materials for the exploration and exploitation of the Solar System [28], including the classical example of asteroidal mining.
Given its proximity to our planet, launch opportunities occur quite often, a matter of weeks compared to years to reach even NEO's: it appears then logical to test stuff such as landing gear and autonomic robotic exploration on the Moon instead of waiting months and months to get the right alignment just to launch towards another planetary body [29].
Economical to reach, economical to land onto and depart from, and with frequent launch windows, the Moon's main strategic scientific and technological value may indeed lie in where it is [30]: "near but not here".
As an example, the Moon is a much better place than Earth to bring back Martian dust and rocks in a Sample Return mission, as chances of contamination of the specimen by Earth living organisms would be dramatically reduced (just as the risk of any Martian life to roam unchecked our planet) [31].

Geopolitics of the Moon

But even if the Moon is indeed unique for certain undertakings, our only effective example of its exploration is the 1960's Space Race between the USA and the USSR, when the "why" was purely a matter of political prestige to be gained by one superpower over the other.
We all know that race was won by the Americans. Little more than twenty years later there was no USSR left at all. From our 2004 point of view it can be argued that the USA effectively sealed their commanding status over the rest of the world by achieving the Apollo 11 landing.
If that is true, the first nation to return to the Moon will then either keep or destroy a huge chunk of American prestige.
If the next moonwalker will NOT be an American, commentators will have enough to seriously start talking about, and people to seriously start believing into witnessing the "End of the Empire". Just like in 1969, it is obvious that the entire geopolitical situation on Earth will appear wholly different if, for example, a local Chinese crew were to welcome in 2030 the first NASA manned mission to the Moon since December 1972.
Curiously enough, the present stalled situation, with the American Lunar capability dismantled and the potentially Moon-bound Saturn V machines gathering rust in open-air museums for political reasons, strongly resembles the 1400's Imperial Chinese Navy, destroyed by the Emperor after having explored (and effectively subjugated) much of the Indian Ocean decades before the Portuguese [32].
We all know that "race" was won by the Europeans. Little more than three hundred years later there was no Chinese imperial dominance left at all.

Social significance

Those apparently heartless political calculi of national prestige are (also) based on the very tangible social impact of "adventurous" manned space flight (i.e. the one where the astronauts effectively do go somewhere apart from orbiting Earth).
No better evidence about it could come than from Buzz Aldrin's own words when being shown a recording of the TV broadcast of the first lunar landing: "We [Aldrin, Armstrong and Collins] missed the whole thing". Grown-up commentators became so emotional to literally have to wipe off their tears in front of the first examples of planetary-wide audiences. The USSR's Pravda couldn't help printing the news in its front page, however small. Space exploration with humans is an endeavour that fascinates and enthuses all of us. It brings hope and shows that it is possible to "do the impossible". Generations have been born already for whom the proverbially impossible "flying to the Moon" is a reality.

Those generations are as sophisticated as any, though. As shown by the cool reception of President Bush's space initiatives, it will be much harder to convince them to go back to the Moon without a very healthy dose of pragmatism.

Humans or Robots

As quite often heard, humans ARE indeed costlier and riskier than robots. Environment control is easier in an automatic probe, there is no need to carry food not to recycle waste, etc. etc.
Still, in the history of Lunar exploration it would be hard to argue the unique advantages that humans bring to fieldwork [33] [34].
Take for a start Apollo 16: it was a mission conceived, designed and organised to collect volcanic rocks from an area consensually believed to be volcanic. It wasn't, but the astronauts were quickly able to focus themselves on collecting what was needed to understand the local soil [35]. Would it have been the same for a robot programmed specifically to investigate volcanic rocks?
Another example: the so-called KREEP rocks, unexpected, new and enigmatic collections of Rare-Earths [36]: would a rover (even as sophisticated as those in use in the XXI century) have been able to bring that back? Just as for Apollo 17's "orange soil", hardly a feature of any orbital mapping or automated lander's photograph.
Robots, of the kind feasible in the foreseeable future, can only do what they are programmed to do, so they will only examine and report according to their limited set of instructions…consider the Galileo space probe, designed to study Jupiter: as it passed by Earth in the early 1990's, it managed to get only hints of the existence of biological life (as gases in the atmosphere) and technological activity (as radiowave emissions).
Combine this with Mark Twain's musings: "there is something fascinating about science. One gets such wholesale returns of conjecture out of such a trifling investment of fact.". Years can be wasted (and important data remain uncollected) simply by building and sending robotic probes built around the wrong conjectures.
The only practical way to discover and understand something new (apart from chance) is by sending people [37].
We can generalise that people are needed where research would otherwise be prohibitively difficult [38]. And as the recent debate about repairing/upgrading the Hubble shows, humans are still too hard to substitute when there is the need for a complex upgrading or repair of instruments. From a Moon base, astronauts would be well placed to reach the new generation of telescopes built for one of the Sun-Earth Lagrange points [38]. Sure, their presence may degrade the natural lunar vacuum, but even with minimal precautions we have reasons to believe it will still be better than on Earth [39]. Finally, a Moon settlement is an alternative rest/rescue station from LEO operations [40].

Commercial Moon

Clearly the full-scale colonisation of the Moon may start and be much encouraged if feasible commercial reasons could be defined.
We have already mentioned the mining of materials for LEO and for solar system exploration: this could include the rather easy-to-extract lunar soil oxygen [41], ready to be sold to space transportation systems unwilling to carry it all from Earth surface. There has been much talk for years about extracting the exceedingly rare Helium-3 from the lunar soil as clean fuel for nuclear fusion reactors [42], but this may be classified as a non-reason as the first customers won't materialise for five or more decades.
Given the fascination astronautics has with the public, with the right kind of infrastructure in place there will undoubtedly be lunar movies, documentaries (e.g. IMAX's documentary about the ISS). And if costs for Earth launches and return trips will be lowered by a factor of 10 to a 100, tourists [43] will be able to start travelling to a Moon offering new kinds of sports, the chance of flying using one's own strength, and acrobatic shows featuring "impossible" feats. Furthermore, it will be in a low-g environment that would benefit all and especially those helped by hydrotherapy.
We do have an example of a one-g town built out of nowhere and quite good at self-sustainment at one-g, and it is called Las Vegas.
In the wake of plots of lunar land allegedly being sold on Earth, a market for memorabilia is expected, including moon dust, moon rocks, but also recovered items such as Apollo 16's forgotten film.

Legal environment

Short of transforming the Moon into some kind of frontier town, the settlement there by humans and the development of a lunar economy will need a legal framework agreed and understood by people and nations and companies alike. We will analyse this in next section. For the time being let's consider some legal reasons for going to the Moon.
In fact, many points about the legal conditions of all space activities need to be clarified, and historically those clarifications have come out from specific initiatives. For example the American effort at flying a satellite during the International Geophysical Year 1957 was sponsored by the government as a way of setting a precedent regarding over-flights [3] (and it worked). However trivial it may appear, there is an ongoing court case about the right by a certain company to claim ownership of the surface of asteroid Eros, and as such to be able to collect "parking fees" from NASA, that landed there one of its probes. Not to mention (at least for now) the Lunar Embassy, self-proclaimed owner of all planets and satellites apart from Earth, and the counterclaim by somebody asking for an "illumination fee" as sole owner of the Sun. Hardly stuff worth involving some Supreme Court somewhere, and yet the simple fact that all of this may even happen is the clearest sign that legal precedents and agreements need to be set.
And the longer they will not be, the less serious the whole idea of space travel will appear.

Issues

As yet nobody has been on the Moon for more than 30 years. All the reasons above have been somehow effectively nullified by counter-reasons. Among those, changing political climates especially in the United States (there is little if anything worth mentioning about other nations anyway). Bush Sr.'s space initiative was rapidly forgotten by the newly instated Clinton. And of course we are living in the shadow of Nixon's decision to concentrate on developing the Space Shuttle thereby making obsolete the successful Saturn V and shortening by several hundred thousand miles the range of manned space travel.
For years much has been done about humanity's fascination with (if not obsession about) finding life [44], thereby undermining all plans about returning to the Moon. Maybe it is only now that the idea that one needs not promote a single target for astronautics to expand: let's hope that NASA's exploration culture will not become a version of "All eggs in One Mars". On the side of lunar and planetary scientists there have been few examples of effective, politically aware and timely pressure on. At the time of the cancellation of Apollo 18 and 19, it can actually be argued that had the scientists lobbied Senators and Representatives early enough with the strength displayed when protesting against the decision, one or both those missions would have actually happened.
Or perhaps it was the Apollo era to be uniquely special. Within this interpretation, before and after Apollo the Moon [45] has simply been neglected because [46]:
– too close
– too easy
– too dead
– too "well-known"

WhatTechnical areas that will have to be dealt with to establish a permanent lunar settlement include travel and construction technologies, but also organisational, financial, legal and political aspects. Also, who do we expect will inhabit the Moon? And where will the settlement be built?
The following section analyses some of the issues involved: anyway, as the Apollo experience shows, what will actually happen will depend on circumstances simply unforeseeable (e.g. Saturn's S-1C's size being dictated by the make-up of the factory where it was going to be built [47]), including apparently insurmountable problems that will be solved when necessary.
As such, the minutiae of the technical details are not warranted the attention given instead to the overall outline of the what.

Technology

Given the accumulated experience it may appear more likely to be NASA leading the way towards a return to the Moon. President Bush's plan described in December 2003 does indeed call for a manned mission after a series of robotic rovers. It remains to be seen if this plan will go the way of so many others: clearly there is still a difference between recurring, partisan calls to space and a grand vision outlined as a fight for national survival by a young, prematurely killed President. With NASA following orders more than leading consensus on space exploration, it will be a hard call for presidential staff changing every 4 or 8 years to maintain the same policy about space flight for many years in a row.
How about forgetting the politicians then? Private space travel [48] is likely to be somewhere in the middle of its infancy, with the famous X-Prize perhaps going to be won by 2005 or 2006. Some companies are already planning cargo flights to the Moon and appears ready for the undertaking as soon as the right number of clients is achieved: Transorbital's Trailblazer and Orbital Development's MoonCrash. Definitely primitive stuff compared to a 1969 human landing, but no doubt progress will be made quickly were a viable entrepreneurial case be made (or found…), for example in providing services to the lunar settlement, starting with a detailed lunar map.
Space travel aside, a lunar settlement will have necessarily to be tested at first as a terrestrial mock-up [49]. For the beginning it may be appealing to simply re-use ISS technology, with slight changes to accommodate a non-zero gravity environment. But the endeavour will be viable only by development of ISRU (In-Situ Resource Utilisation): in other words, transport the building machines, not the goods [50]. Several studies indicate that lunar regolith can be used for construction, apart from extracting basic materials such as oxygen and iron. Water for making lunar cement and other manufacturing purposes may come from polar craters if confirmed (and if reachable): otherwise there may be a case for a thorough investigation of available small-size, water-rich NEO's.
Surface and local transportation of goods and people may involve ballistic trajectories on the airless Moon, and/or building of regolith-resistant railroads. It is also not difficult to imagine way-stations on Lagrange points acting as transmitters for some kind of lunar GPS (low-orbiting satellites not being viable due to uneven mass concentrations Mascons near the lunar crust)
Other important details include telecommunications (likely of the photonic variety wherever possible); power generation and distribution, with polar or orbital solar generators perhaps as first tests of microwave energy transmission across vast distances before implementing that technology on Earth.

Inhabitants

Much has been made of the fact that of 12 moonwalkers so far, 11 were not scientists (and the only one has been effectively sent at the last available opportunity). Apart from the very beginning, it will be difficult to maintain such a disparity in favour of professional astronauts. Next to the scientists there will likely be other service personnel (again, not only astronauts), all of them likely in monthly or quarterly shifts. With the settlement becoming more suitable to human habitation, visionaries/entrepreneurs will then lead the way to tourists, explorers, TV crews, etc….and to dubious characters, including bounty hunters (why expect men on the Moon behave much better than on Earth?)

Organisation & Financing

If the settlement will not be almost entirely devoted to political considerations, it will be run by an international public/private consortium [51] among all those entities aiming at benefiting from using the Moon. There are several possible examples on Earth, such as having a "Lunar Port Authority" or even a Lunar Economic Development Area [52]. It has been proposed to finance the enterprise by issuing bonds, however in general creative and effective ideas in this field (short of getting the taxpayer foot the vast majority of the bill) are still in short supply.

Legal and Political structure

It has been argued that if Intelsat is the appropriate precedent, there are no additional legal problems for lunar profiting [53]. However, as said above there are several possible legal hurdles to pass, including the "land ownership titles" sold by the "Lunar Embassy" to around 40,000 clients.
However idiotic the situation may appear, only a small percentage of the 40,000 would be enough to warrant some huge legal headache to any Lunar Port Authority, unless the related treaties are amended according to common sense.
Other legal bounds make much more sense. It should be clear to everybody working on the Moon that the unique local environment should be left as much untouched as possible [54], at least for scientific reasons [55].
This is a rather difficult endeavour. Apart from conservation of the historical sites, the extremely tenuous atmosphere is easy to be disturbed. It was for example doubled in mass by the exhausts and leaks of the Apollo missions.
It should also not be dismissed the call for the "conservation of the regolith": after all it has taken billions of years to "create the regolith"…as such it shouldn't be simply considered raw material or disturbing garbage. Again, it is all going to mean a revision of the international laws and politics about the Moon. At last, we may even get a new Lunar Treaty [56].

As for the local decisional structure, the best example appears the flexibility of the Antarctic base [57]. Hopefully certain ideas about social engineering, like attempts at founding the "perfect community" on the Moon, will simply remain on paper (or rather isolated)

Physiological considerations

It has been computed [58] that on average a maximum 20% of time should be spent by humans outside the protection of a minimum 4 meters of regolith. This should not be difficult to achieve, and there is anyway a good deal experience on the physiological needs of people, thanks to the work on the ISS.
Debates flare at times on the effects on muscles and bones of low-g compared to the known issues after long exposure to zero-g: a continuative presence on the 1/6g Moon would answer many questions, with implications including the planning of human activity in the 1/3g of Mars.
Some consideration (again not wholly unrelated to a Mars trip) should be also given towards making the atmosphere of the base as dust-free as possible [59]

Location of the settlement

Everything considered, the initial location is likely to be polar or equatorial, the only areas where orbit access is every 2 hours [60]. Traverses between pre-delivered rest-stations (like in Antarctica) could be organised to explore more [61].
And while it is true that in general an equatorial base would be easier and safer to reach from Earth, on the other hand a polar location is preferable, as it means smaller temperature variations, and probably water, with half of the sky (maybe even the Sun) continuously visible [62] [63]

Underground Habitable Structures

A particularly interesting area of study concerns the establishment of inhabited structures several meters below ground level.
Those are ipso facto shielded from both cosmic rays and UV radiation. There is little cross-contamination with the surface. They are protected from impacts, and harder to sabotage. The bedrock is easily accessible, for example to anchor equipment. More lightweight materials can be used and construction much simplified. Plastics need not be protected from UV degradation. Finally, such a structure is repeatable in the establishment of colonies and outposts anywhere in the Solar System.
On the Moon, underground structures could be housed, at least initially, in one of the "lava tubes" [64][65], of which there are many [66], some hundreds of meters long and with 10 meters or more of roofing material. Given the relative size with similar features on Earth, it may even be expected whole huge cave-like "tubes" to be available somewhere on the Moon. Alternatively, there have been already investigations on melting-while-drilling techniques [67], or even excavation through detonation (given the absence of water in the rocks, it is expected that the roofs of artificial caves will not collapse as it would happen on Earth) [68].

P.O.L.E. Peak Of Light Eternal

The P.O.L.E. concept (Peak Of Light Eternal, poetic licence taken) combines the advantaged above in the establishment of an underground polar settlement.
Possible locations depend on a detailed mapping of the polar regions: for the time being they may be the rim of the Peary Crater, or the flanks of the Shackleton Crater at the lunar South Pole. An earlier version was described as a 5-mile-long structure, 3200ft wide and 1600ft tall [69].
With plenty of space available, P.O.L.E. inhabitants would live in large Earth-like caves illuminated as if in the full glare of the Sun. They would not have to continuously look at the Earth outside their windows, and would not experience as much "longing back home" (as for example some Apollo astronauts). They would not be reminded of the Moon "desolation": still, the Earth, the lunar surface, the far-side would be available at short distance.

WhenThe science of astronautical forecasting is very imprecise, with grand targets being notable mostly for their continuously postponed delivery targets (again, the only exception is Apollo). Using past timescales as guidance, there is all the chance that we are in for a very long wait. How can we speed things up?

Current Initiatives

The latest "American President" Plan includes an Orbiter in 2008 and a Lander in 2009 [70]. It should be noted that at least 5 years are expected between the decision and the landing, despite several orbiters and several landers having been sent toward the Moon already (and despite several rovers having landed or getting readied for a Mars landing). General consensus is to send robots to explore the surface, without people at least for another decade [71]. On the private front, Transorbital appears ready to go as soon as the financial situation is right, and others are claiming to be more or less near a launch.

Lessons from past estimates

But it is hard to believe in any published timescale of space exploration as for decades almost every estimate has been proven very wrong, starting from several American President space initiatives (including the Space Shuttle), all the way down to grand promises by folded companies (e.g. Luna Corp, Applied Space Resources).
Truth is that without the USSR there is no race [72], so aims are achieved too late and over budget…if they are achieved.

Infrastructure development

All in all, we can only expect (very) long timescales.
Even if a minimal infrastructure has to be thought-through and readied, there is no sign as yet of an effective long-term exploration planning. For example the Martian satellite Deimos is a neglected body despite its extremely easy accessibility [73] and the fact that Mars exploration and a manned Mars mission are generally considered much more interesting [74] for the public than anything the Moon can offer.
If the politically baffling, even naïve Mars First vs. Moon First debate will be considered a zero-sum game both goals will suffer, with the Lunar projects being most neglected.
And yet, consider also that Mars Society's brilliant efforts and high visibility have brought lots of attention but little practical return on their ultimate goal: there is no plan for a manned Mars trip for a long time to come.
How much more difficult a Lunar equivalent, as evident in the sadly sterile campaigning by moonwalkers Aldrin and Schmitt?

The above can only suggest an even slower implementation of any return-to-the-moon plan. We can reasonably assume that, in the absence of another version of the Space Race, either between nations or between corporations, there will not be any attempt at human landing, let alone at starting the construction of a lunar base before the end of next decade.

Timescale shortening

With forecasting after 2020 as true as meaningless, and too many reasons to go to the Moon to simply consider the whole situation hopeless, let's give a target for the establishment of a permanent manned settlement by 2069 as a tribute to Apollo 11.

Still, there is the possibility of accelerating things by carefully using the acquired experience. A good example is the Clementine mission, designed and built by a small team in 20 months instead of several years.
Even if carrying "sub-optimal" experiments [75], Clementine has shown what can be done when delivery time is key. In general, the less the effort in developing new technologies for new missions, the shorter the time-to-launch (compare to Clementine the years wasted in developing the never-flown X-33).
One may even argue that nothing will really happen as long as Astronautics remains the realm of untamed R&D, with every new mission breaking new grounds: it would be interesting to see if research engineers will prevail over scientists and entrepreneurs [76]. In the meanwhile we can acknowledge that the only means to reach the ISS is the rather old technology of the Soyuz.

Side-effects of long timescales

With long timescales expected, we have to consider how the situation will look different several decades into the future.
Robots will of course get better. Advancement in robotics and telerobotics could effectively nullify some of the "why" points, decreasing the chances to develop the human colonisation of outer space by removing some weight from the whole concept of manned space exploration.
From this point of view a push for having humans explore the Solar System as soon as possible, starting with the Moon, is of the outmost importance.

In any case, it is difficult to imagine any robot becoming better than a human in field studies and the investigation of the unknown.

ConclusionsSome open issues still need to be solved. What will be the economy of permanent settlements? How often do we want to use the Moon? (This would have consequences on the choice of expendable vs. reusable vehicles). What will be the security needs of a Lunar base? (a whole new subject to investigate)

Negatives considerations remain aplenty. Sarcastically, some have said that we should go to the Moon by stacking up all the papers written about how to go to the Moon: or perhaps, all future attempts will be buried by their own bibliography.
In the meanwhile humans are developing astronautical experience by working in the wrong place, disturbing zero-g experiments in LEO instead of exploring beyond Earth orbit [77]. The Space station is replicating the Shuttle in over-promising, over-running and under- (or even un-) delivering.

All more the reason to consider the "why" the most fundamental point about establishing a permanent manned colony on the Moon.
The "what" is anyway heavily subordinate to the "reasons". The "when" depends on our capability at making an effort to achieve our goals instead of developing technologies for their own sake.

As such it is important to prioritise lunar action over plans and studies: enough with optimal missions, big probes, complex new, perhaps too advanced technologies…

Just do it!

As it is hopefully going to happen thanks to initiatives such as the Artemis Society and SpaceFuture's space tourism plans.

Is that going to herald a cultural change in the public space industry as well [78]? Will all the people, societies, companies involved in Space be able to build public interest into a long-term solar system exploration plan, postpone if not outright stop public squabbling and get into the business of actually going to the Moon?

With robots able to do and humans able to explore, and years needed simply to wait for a launch window outside the Earth-Moon system, lunar astronautics may as well be a way of keeping astronautics going instead of waiting for uncertain Mars missions while wasting away making LEO orbits.

Perhaps one day this will finally start to happen: maybe an innocent will rise and people will say, in the words of Bridget O'Donnell, "she didn't know it couldn't be done, so she went ahead and did it"

Abstract submitted for the upcoming BIS symposium on "Human Future and Space"

This proposal covers the establishment of permanent lunar polar settlements, enriching the residents' quality-of-life by exploiting a low-gravity, controlled-atmosphere environment. Senior citizens, paraplegics, and patients recovering from major accidents are among the possible target groups. A temporary or permanent stay (roughly comparable to hydrotherapy) will extend and improve their lives, by helping the respiratory and circulatory system, facilitating rehab activity, lessening the chances of contracting infectious diseases, and making movements easier, with the added opportunity to explore the Moon (and to fly with one's own muscles). The settlements are built within terraformed caves of approximately 5km in diameter, simulating an Earth-like panorama